Additive manufacturing techniques such as three-dimensional (3D) printing, relate to techniques for making 3D objects of almost any shape from a digital 3D model through additive processes, in which 3D objects are generated on a layer-by-layer basis under computer control. A large variety of additive manufacturing technologies have been developed, differing in build materials, deposition techniques and processes by which the 3D object is formed from the build material. Such techniques may range from applying ultraviolet light to photopolymer resin, to melting semi-crystalline thermoplastic materials in powder form, to electron-beam melting of metal powders.
Additive manufacturing processes usually begin with a digital representation of a 3D object to be manufactured. This digital representation is virtually sliced into layers by computer software or may be provided in pre-sliced format. Each layer represents a cross-section of the desired object, and is sent to an additive manufacturing apparatus, that in some instances is known as a 3D printer, where it is built upon a previously built layer. This process is repeated until the object is completed, thereby building the object layer-by-layer. While some available technologies directly print material, others use a recoating process to form additional layers that can then be selectively solidified in order to create the new cross-section of the object.
The build material from which the object is manufactured may vary depending on the manufacturing technique and may comprise powder material, paste material, slurry material or liquid material. The build material is usually provided in a source container from where the build material needs to be transferred to the building area or building compartment of the additive manufacturing apparatus where the actual manufacturing takes place. WO 2007/139938 A2 (CORP Z [US]: DAVIDSON THOMAS [US]; HERNANDES ANDRES T [US]; KINSLEY J O) describes means of transporting powder from multiple sources to a powder dispensing apparatus. US 2011/083768 A1 (SIMS DAVID M [US] ET AL) relates to shipping and off-loading of a granular, powdered, or other particulate materials using flexible containers.
For simplicity and clarity of illustration, the same reference numerals will be used throughout the figures to refer to the same or like parts, unless indicated otherwise.
The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention.